Prekin,
I'm guessing that the price he gave you is in EUROs, I would go with the LAST quote he sent. Without seeing the actual invoices I couldn't tell which should be correct. Ask him to clarify.
I flew the plane with the Ramoser Varioprop installed, pitch set at 14 inches. I had guessed that the DA 60's rpm would be lower turning the varioprop, it sounded like it was turning around 7,000+ rpm in the air. On the ground the varioprop did not stall at high throttle, like the Graupner 22-12 did. Performance was about the same, I got a speed reading of 79 mph at 1/3 throttle, full throttle level speeds were in the 110-114 mph range. I forgot to take my blue tooth speaker so I had to hold the transmitter up to the plane as it flew by to focus on, and READ the tiny display, not easy, and you can't take your eyes off of the plane for more than a half second to read speeds. My nomograph chart gives an rpm of around 7,400 rpm for 114 mph, and subtracting 6 mph to correct for sensor calibration error still gives 7,300 rpm at 108 mph. I didn't try to get dive speeds, and the prop was ripping at times. All around performance was the same except for absolute altitude reached, the Graupner prop pulled over the top better and probably gained 100-150 feet more than the varioprop. The plane still did more than 3.5 vertical rolls, close to the best Graupner performance.
Take off and landing handling seemed to be better with the varioprop, there was no tendency to ground loop as the tail came up, and landing run outs were straight. I use a throttle curve for precise throttle control at low speeds so the liftoff point and climb-out was reached at 1/4 throttle true, below the speed that the speed sensor starts working (around 19-21 mph). It was the first time that I did several touch and go landings and had every one be a grease job. All of the takeoffs and landings were done on the grass except for the last landing on the blacktop, and it was a greaser too. I think the wide blade varioprop makes ME a better pilot. Other guys at the field complimented me for the good flights and especially the landings.
Next, I will paint and decal the prop blades for a more scale appearance (in flight). And I will consider getting a smaller diameter set of blades (19.9 inch) to try a four blade setup that the DA 60 may be able to turn. I had success when I did this with my lower powered 50 cc electric motor setup. The guys also mentioned the plane had better sound with this prop, there is definitely more blade noise in flight below the rip rpm. Cruising by at low altitude at 1/3 throttle and 80+ mph does sound good, the chainsaw exhaust noise is suppressed and the prop noise more audible. I might experiment with mufflers to get less chain saw racket.