$49 is pretty steep compared to a gameboy, which goes for $20, has a massive catalogue, affordable flashcarts, and several decent toolchains (I personally reccomend WLA-DX). And it also doubles as an excellent music production platform (provided you like chiptunes) thanks to LSDJ.

The GBA goes for similar prices, and has similar benfits (and yes, it's got a solid toolchain). Plus, it plays all the old gameboy games, so all of the above applies (although LSDJ is a royal pain to use on the original GBA, as it assumes a standard GB button layout. Nanoloop has a version explicitly for the GBA, which takes advantage of the new sound hardware, but Nanoloop carts are very expensive).