I have the PFD1000 Pro installed. I was looking for an EHSI when the Aspen was announced and with the cost of the Aspen not much more percentage-wise than a new EHSI I opted to wait until the Aspen was available. Despite some early adopter teething problems I've been pleased with the unit. I find it reduces the time for an instrument scan in IMC as it puts a majority of the info you need directly in front of you. I have a 430w and the Aspen allows me to remove the right side data fields on the Garmin for a larger map. I would have gone with a 530w but I am space limited in the radio stack. With an SL-30 as a second nav/comm it's nice to be able to monitor both VORs/LOCs on the same HSI display of the Aspen. Imho, the moving map feature of the Aspen doesn't add much utility if you already have a moving map display, although it is handy when flying an approach as it puts the missed/hold graphic right in front of you. The air data display is an asset giving you winds aloft, TAS, and OAT, which lets you validate accuracy of the forecast winds and possibly find more favorable conditions enroute. I also didn't need to cut any new holes in the panel for the Aspen installation.
I also have a complete vacuum panel in addition to the primary electrical panel on my plane. I replaced the pump, AI and DG back in the spring when the pump died. It seems when a vac pump croaks there's a high probability that carbon dust will be drawn back into the instruments before the pressure equalizes. Don't ask me how I know..
The old DG (~8 yrs old) had a lot of precession that I didn't think was unusual until I installed the new one, which is rock solid and drifts less than 5 degrees in a hour of flying. I didn't want the airframe downtime associated with sending off my instruments for overhaul, so I opted for new ones. O/H costs I were quoted were about 2/3 that of new replacements. (I had the old ones o/h'd and held on to them for a while until I felt confident the new ones weren't going to experience any infant mortality.)
I feel a lot more confident flying IMC now with the Aspen and the vac system updates. That doesn't guarantee against an in flight failure of either, but the likelihood of a simultaneous failure of both is pretty remote, imho. It may appear to be overkill, but I now have multiple heading, airspeed, altitude, and attitude indications, most of which are independent. I also use a handheld GPS for additional flight data redundancy. The handheld makes it handy to download to a computerized flightlog, too.
Below is an image of the unit in my panel during "first light" before calibration. What is not shown is the right side of the panel with the full vacuum instrumentation and duplicate ASI/ALT/VSI (belt and suspenders).
), add it too (the MFD 1000) and you'll have dual AHRS and can toss the mechanical gyros completely if you wish. No more overhauls to worry about, ever. 