Two 777 pellets really isnt even enough to bring the 290gr T-EZ into the fps range that will get you the most benefit from its BC or construction. Pellets are actually the most expensive per shot and fps gained. Two of them isnt exactly impressive in the fps department and three usually don't shoot very well.

If you want to spend top dollar on powder and get performance, use BH209 if your gun supports it. You can save a bunch more with other subs too and just use a tube for the powder. You would keep your extra pellets in a tube or speed loader anyway so they have nearly no advantage.