If you can wait, I think the
TPA3251 (or one of the related chips) will probably pass the tpa311x as the "go to" class-D chip for high value (i.e. good price/performance ratio)
and decent power specs... The summary of that diyAudio thread I just linked is that there are a few folks currently working on PCBs, I think group buys probably aren't too far off. Depending on who does the board, the degree of DIY could be anywhere from "board + bag of parts" to something that just needs to be put in a case and wired to a power supply. But once those get out, I'm betting you'll start seeing various copies, clones and other plug-n-play amps like the SMSL. How long of a wait? Hard to say, I'm already waist-deep in speculation, but just to dive in all the way, I'll say six months.
If you don't want to wait for an unknown amount of time: look for a good implementation of the irs2092 chip. The company "Class D Audio" makes some nice units and are the topic of this thread:
$175 Class D amp--120 wpc. They have both fully-assembled amps, as well as populated boards and power supplies for the DIY route. You can save even more going DIY with the stuff from China (ebay, taobao, aliexpress, etc). See this diyAudio thread
200W IRS2092 Amp for $20 for an example of getting quite a bit of power on the cheap.
