Is the "arduino as isp" a fully-fledged programmer?

Hi,
Is the "arduino as isp" a fully-fledged programmer?
Or does it have limitations like the usbtinyISP?

Thanks!

Short answer: No, not even close to something like a Dragon or a newer type programmer. The ArduinoISP sketch does the SPI mode for Mega and Tiny devices, but will not program AVR's that use the PDI mode (e.g. Xmega). The ArduinoISP sketch is done with a UART interface and therefore works on Linux, Mac or Windows as expected. It is my understanding that the usbtiny relies on a Windows USB hack that does not work on other systems (and who knows when a Windows patch will kill it).

Thanks for the reply!
One more question: Can it program bigger chips that the usbtiny can't? Like the atmega644 or 1284?

Yes I program the ATmega1284p with an ArduinoISP sketch.

Hear is an example of how I load a bootloader (xboot in this case) on an ATmega1284p

The ArduinoISP sketch talks as a stk500v1 ISCP tool, and its baud rate is 19200.

It is my understanding that the usbtiny relies on a Windows USB hack that does not work on other systems (and who knows when a Windows patch will kill it).

Really? I'm using this USBtinyISP, and it has never failed me, not a single time. I'm using a mac, and no drivers where required to get it working with Arduino IDE/avrdude. The USBasp on the other side; not nearly as reliable.

Yep, if it had a proper USB chip (e.g. 16U4 rather than a Tiny) I would probably not confuse them. Well, the ArduinoISP sketch works for me so do whatever.