I would consider the Combi-plan (available new from Freestyle, BH, Adorama, but shop around for the best price) for a good starting option. They can handle a number of sheets at once and work well if you follow the directions. Most of the problems seem to be from people who are not operating it properly and get subsequent slow filling and draining times. Their sales rep is available via email if you have questions; his email address should be on the companies web site. If you get one used, make sure that it is in good shape (i.e. no cracks in the tank or lid, no broken clips, etc.) and that you get everything that was included in the original package. All the parts are available new from the vendor if you need replacements though, so no real worries there if you can't get a complete set.
The Yankee products are notorious for being problematic. I had some Yankee products in the past and the fit and finish never was as good as other brands. I think that they were the 'affordable' option, you know? Anyway, you could also do some research on the 'taco method' of developing, which allows you to develop multiple sheets in one stainless or plastic tank (without reels of course). I use a 4 reel tank for stand development of 4x5 negatives and find it very 'do-able'.
- Randy