I attended and graduated from UTI. The only way I would recommend it is if you have zero knowledge of any type of auto mechanical skills. It's geared towards people who don't have any prior experience, and are starting from 'zero'. I went in with a pretty good bit of know-how, and really didn't walk away from the school with anything in particular. The total cost was about $25k out of my pocket. Their job placement program is a complete joke, when I graduated they got me 'awesome job leads' at places such as Jiffy Lube, Auto Zone, etc.I also don't think very highly some of the manufacturer-specific programs, specifically Nissan.
How can I say that with such certainty about Nissan? Well, for one, I work at a Nissan dealership that's very close to the Houston UTI campus, and we get UTI/Nissan students in here pretty frequently, and they're about as aptly prepared upon arrival at the dealership as someone who's spent a little time on a lube rack.
Honestly, your best bet for getting into the automotive/dealership world? If you have a small bit of automotive experience, even if it's just working on your own vehicles, go apply at a dealership as a lube technician or an apprentice/helper, and work your way up. You'll learn a LOT more hands-on in an actual shop than you EVER will in a classroom, and once you're ready to move up and be a real tech out on your own, you'll already have a dealership job where they know that you aren't an imbecile, and you'll have a better shot at making better money.
Just my .02, from someone who's already been through all this.
edit: and FWIW, in the few months I've been at this Nissan dealership, I haven't experienced a 'slow' time - and this time of the year is generally when the shops/dealerships go into a slump. Shit, I've already flagged close to 10 hours today and I've only been here 2 and a half hours.