The processing is both at a very high level. It's hard plastic in place and the parts that are made of plastic, but look very high quality. The handles are the Rennkompressor of wood, which will probably last forever, but they are not particularly ergonomic shape. When Airmenius are top ergonomic cork grip that was far better in the hand.
Another advantage of Airmenius is the extremely long excerpt, even at 2m height could it probably comfortable use. Through this long extract you get a relatively large amount of air a few pump actions in the tires. When Rennkompressor the extract is not so huge, so you have much more often with him pumping. Compared to a pure mountain air pump but both have a relatively weak pumping power, it thus creates a mountain bike air pump only to about 4 bar. The two go supposed to just over 12 bar, but I only need 8 bar, so I can not judge.
But since I need the pump for road bike and MTB, the large gauge of Airmenius for me is a significant improvement. When Rennkompressor I found it difficult to read, whether now are 1.5 or 2 bar on the tires, but what makes a big difference in a mountain terrain. The 10cm wide gauge of Airmenius but you can read without problems without having to bend down, one can easily read even in 0.1 bar increments.
The only downside is the size of Airmenius if you often transport the pump, the retractable feet of racing compressor are certainly an advantage. But since I have to 99% in the cellar my pump me that is relatively unimportant.
In conclusion, I can only say that I have to upgrade to Airmenius no regrets. I can not imagine that there is still a much better air pump me. For me as a passionate cyclist, the investment has been worthwhile certainly, that I will thus probably a few more years have a joy. The only reason for the Rennkompressor would in my opinion, only the price and the size.