IMHO, PICBASIC will be the one to choose. It's on the market since awhile, mature and stable.

On this forum there's a huge amount of people to help you on various area.

Look at the Supported device list of PICBASIC PRO.


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Atmel are great but, i doubt you'll find support as here.

Microchip always growing, there's a HUUUUUGE amount of different device, different size, different speed up to 48MHZ, and, and...

Well choice is still yours