You will not be saving money servicing one regulator as you need tools and training. So just look what you can get serviced in your area.
The regs are also not a life support system
First, you don't actually need training. Buying either "Regulator Savvy" or "Regulator Maintenance and Repair" will teach you what you need to know. Second, the cost of tools you have to buy is typically less than the cost of one servicing, assuming you have any tools at home. If you have no tools at home, it's about equivalent to the cost of one servicing. Sure you can spend more on tools but what's the point? Third, I have no less than 2 first stage and 3 second stage regs that shops in my area simply won't service. I bought those three regs for about $40 total and by the time I'm finished I will have spent less than $100 to service all three and have enough spare parts to service them again next year. (That's less than I spent servicing my Scubapro Mk10/G250 one time at a shop.)
As for particular makes and models, it really doesn't matter if you're going to service them yourself. I did a bunch of research on here and asked for recommendations if I knew model numbers. I ended up getting mediocre to good gear for good prices. I currently have the scubapro setup mentioned above. I also have an AMF/Voit Swimaster MR12 II first and second stage (nice little reg) and a Dacor Pacer 900 first with Pacer and Pacer XLE seconds. The Pacers are generally considered "lower" end but they seem to function just fine... not as smooth/easy breathing as the scubapro but I paid less for them and expect less from them. These are going to become my brother's kit and he's certainly not going to complain about free gear.
I recommend looking in the DIY section and reading as much as you can about servicing various units. Lots of info on why people are choosing the 109s for example.
Here are a few links for the OP from threads I've started here on scubaboard asking about servicing regs:
http://www.scubaboard.com/forums/bo...sus-harlows-regulator-maintenance-repair.html
http://www.scubaboard.com/forums/repairing-your-own-gear/408934-sources-parts.html
http://www.scubaboard.com/forums/repairing-your-own-gear/407614-tools-regulator-maintenance.html
http://www.scubaboard.com/forums/re...rosion-metal-reg-parts-how-much-too-much.html