I have one and it's much prettier and much more user friendly than the GRT dual horizons with trutrak etc that I used in my second homebuilt.
That being said, the GRT gives a heck of alot more info, i'm still new to it.
The EFIS one I have circa 2004 is beautiful for local stuff with airspace all over the place. Better than lookswise to any GPS i've seen G1000, chelton etc... to a point.
A grip is the inability to scroll out on the terrain GPS screen.
I have lots of picts of my EFIS in air on my photo dump if you have time.
also, a negative is the huge computer on the "Gold box" versions. just heavier etc. old tech. HSI is wonderful to shoot ILS's with.