Although on a map of Frankfurt the hotel does appear on the eastern edge of Central Frankfurt, U-Bahn lines u6 and u7 (after a transfer at Konstablewache) provide convenient access to the hotel. From the Zoo stop it can be a long walk if you have a lot of luggage, but if you take the u7 and get off one stop past the Zoo there is a smaller more conveniently located station there.
If you have business in the area of the Messe or need to get to the Hautbahnhopf early in the morning, a hotel more centrally located would be a much better bet, but as I was staying during the World Cup and desperately hoped to avoid the crowds, this hotel was the perfect choice, and fairly priced (about 125 EUR). I imagine that during low season you might be able to get even lower rates.
The hotel itself is (as previous reviews state) in a quiet neighborhood, with a supermarket located nearby (good for stocking up on fruits, rations, water, beer), as well as a fantastic Italian restaurant whose food is excellent and prices reasonable (7-10 EUR each). The zoo is a little bit pricey (8 EUR) but a possible destination if you are travelling with children.
The room I stayed in appeared to have been recently renovated, but it was a terrific room, much larger than the one in another Best Western hotel where I stayed at in Frankfurt. Huge king-sized bed, large TV, a mini-bar, large writing desk, comfortable chairs and large windows, air conditioning (this can be crucial in the summertime), a larger shower and bath area with two sinks. An ideal hotel for couples or families. Also, hangers, fluffy towels, rubber ducky (placed on the towels each night, for decoration only), and in-house electronic safe. Very excellent cost-performance.
Staff there are helpful and friendly. Be sure to ask for the Hotel Gast Card on there if you want to buy a two-day pass for the Frankfurt U/S-Bahn transport network, a steal at only 7,40 EUR. At the front desk you can also read English newspapers (Wall Street Journal, Herald-Tribune.)
Strongly recommend this hotel.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.