In comparison, the tamiya kit is better than the minihobby kit...but by a small margin, and the price is well...somewhat inflated.
I've read negative reviews of the PT-815, but I found all three examples that were sent to me to be fine kits, easily convertable from the r/c model to a static kit, and said so in my review of them. Especially for the price, it is a fun build, requiring just a little modification.
http://www.ewaldbros.com