Buy the .357 - then you can shoot 38's too. Two guns in one.
I have the .38+P version...and installed an XS Sights Tritium front night sight myself. Honestly, I would stick with the .38+P...there's plenty of punch, especially with CorBon 115 grain rounds. Scoring accurate hits, with somewhat less power, is more important than a heavier round in my book. I like the light weight and accuracy that the LCR in .38+P provides.