The Powermax1000 is a 60 Amp unit, while the Powermax45 is a 45 Amp unit. On materials thicker than about 1/4" the 1000 has more power, and also has thicker piercing capability. When using the FineCut consumables..the cut quality is nearly identical to the Powermax45 on thinn materials.
The 45 has better consumable life and better edge angularity (from my experience).
Regardless.....for the price you will be getting a great bargain, especially with both hand and machine torches!