When comparing µTorrent vs Tribler, the Slant community recommends Tribler for most people. In the question“What are the best Torrent clients?” Tribler is ranked 21st while µTorrent is ranked 23rd. The most important reason people chose Tribler is:
Tribler has a built-in, extendable search.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Lightweight
Weighs just barely over 1MB. And while it's gained a bit of feature creep over the years, it's still a lighter-weight client than many of its competitors.
Pro Full-featured
µTorrent covers basics such as Prioritization, Selective Downloading, DHT, PEX, LPD and Magnet URIs as well as Broadcatching, Sequential downloading and Search. It includes MSE/PE for security. It has graphical and web interfaces. Has UPnP, NAT-PMP, NAT traversal for automatic router configuration. Has UDP tracker and µTP data transfer protocol support. Even covers IPv6, web seeding, Embedded tracker, Super-seeding and proxy servers. And it auto-updates.
Pro Clean and easy to navigate user interface
A clean, visually-appealing interface that’s incredibly simple to navigate and cuts down on clutter by allowing any element of the UI not needed to be hidden.
Pro Doesn't slow down other Internet activities
The application automatically manages bandwidth it takes up to not get in the way of other Internet-dependent activities.
Pro Portable
µTorrent can be run without having to be installed as it stores all files and settings in the same folder. It can be put on an external storage device (such as a USB drive) and run directly from it.
Pro Built-in search
Built-in search engine allows finding torrents to download right from withing the torrent client.
Pro Cross-platform
µTorrent is available on Windows, Mac, Linux and Android.
Pro No website needed to find torrents
Tribler has a built-in, extendable search.
Pro Uses P2P onion routing to provide anonymity

Pro Has a p2p search engine that can never be taken down
Pro Free and ad-less
Tribler is free and completely ad-less.
Pro Full-featured
Tribler covers basics such as Prioritization, Selective Downloading, DHT, PEX and Magnet URIs as well as Broadcatching and Search. It includes MSE/PE for security. It has graphical, web and command line interfaces. Has UPnP, NAT-PMP, NAT traversal for automatic router configuration. Has µTP data transfer protocol support. Even covers web seeding and embedded tracker. And it auto-updates.
Pro Video-on-demand
Watch your videos while you download them.
Cons

Con Proprietary
No source code is publicly available. As such there's no way to independently check what security and privacy features are implemented and how as well as whether there's any malicious code or not.
Con No tracker exchange
Tracker exchange functionality allows peers to exchange information about trackers of a given file. It is another way of ensuring that the file is downloaded from the optimal source. µTorrent lacks this functionality.
Con Are known to bundle riskware
In additional to typical toolbar and ad bundles, µTorrent has previously bundled an automatic cryptocurrency-miner called EpicScale even if the user opted out of other bundled software.
Con Inappropriate ads (can be disabled)
Not only does μTorrent have ads in the free version, they tend to be inappropriate ads for scammy things like "meet russian women".
Ads can be disabled in the options. It's important to note that disabling ads (as well as all bundled software and featured content) can be a difficult process as it requires manually editing multiple key/value pairs in advanced settings.
The following keys have to all be turned to false by going to options > preferences > advanced:
bt.enable_pulse
distributed_share.enable
gui.show_notorrents_node
offers.left_rail_offer_enabled
gui.show_plus_upsell
offers.content_offer_autoexec
offers.sponsored_torrent_offer_enabled
offers.featured_content.badge.enabled
offers.featured_content_notifications_enabled
offers.featured_content_rss_enabled
Con Bundles bloat
Installation wizard starting with version 3 offers installing a variety of garbage features including toolbars and ads. And makes the process of opting out of such bundled software difficult. It's possible to find version 2.2.x online (1,2) - same lightweight, feature packed application without all the unneeded extras or ads.
Con Highly questionable developer competence
On December 2014, Yawning Angel did a casual code analysis and found a plethora of Tor protocol flaws and implementation issues calling in question their general quality assurance practices and code quality.
Con Lacks IPv6 support
Con No super-seeding
Super-seeding is an algorithm used to allow downloaders become uploaders quicker. Tribler lacks support for this functionality.
Con No local peer discovery
Con Files can't be downloaded sequentially
Sequential downloading can be used to stream media files such as video and audio while the download is still in progress. Transmission requires waiting until the complete file is downloaded before it's ready for use.
Con No tracker exchange
Tracker exchange functionality allows peers to exchange information about trackers of a given file. It is another way of ensuring that the file is downloaded from the optimal source. Tribler lacks this functionality.
Con Lacks NAT traversal support
Con No UDP tracker transfer protocol support
