Mcintosh, Krell or Mark Lenvison Power amps

Look at Pass 250.8 or 350.8 a much better sounding choice.

Levinson, then Mcintosh.  Not a fan of the new Krell.  IMHO.

Krell was the go to when the Apogee's were new. FWIW, I much prefer Krell to Levinson and especially McIntosh. Depending on the particular Apogee's keep an eye on the specific minimum impedance. Not all of these amp manufacturer's amplifier models are necessarily suited for all Apogee's. You might want to consider some Classe' amps as well, though personally I still prefer the Krells. 

Old Krell Class A power amps were made for Apogee speakers.

As I wrote in another thread, Sanders Magtech.

Another Krell vote from me.  I have a pair of KSA 250s powering my Divas.  Been happy with them for about 25 years now.

Hello, looking to upgrade power amp. Can you tell me if I should be looking at amps the can handle 2 ohm loads accurately ? 

It depends on the particular model of Apogee’s. You might need an amp that can deliver power into less than 1 Ohm! Or not, again depending on specific model.