The datarate in upload is simply to low 384kbps, most m2m applications need a higher upload, instead of a download. e.g. camera's.
Companies like a Telit, wavecom, cinterion and enfora, etc.. their main focuss is 2G, but for not being left behind, they all develop 3G. Resulting that the prices are just to high because of the low volume, stay for a long time with the same chipset (investment) and most important, the module is buggy.

This you don't have if you go for a sierra wireless or an option module.
Sierra Wireless have announced a module with LTE (4G) mid 2009