Congratulations on your new RV purchase. This reply is for refrigerator cooling issue, only: We have a Dometic 3-way refrigerator in our 2001 Pleasure-way Lexor.
1. Cooling ability: Due to age and model difference, the performance of our refrigerator may not be comparable to yours, however, we have found as have many other class B owners that we know that the 3-way refrigerators can reliably keep food at approx. 40 degrees or lower when outside temperature a below 90 degrees F. Once temperatures are above 90, depending upon a variety of factors (including sun exposure to refrigerator side of RV and/or whether we are running the air conditioning in the RV), keeping the refrigerator temperature 40 F or lower is not reliable. (Even under these conditions, however, our freezer continues to stay lower than 32 F.) In these conditions, we keep out food that requires refrigeration in a cooler. We have no trouble keeping ice for 3 to 4 days in our $40 Coleman "3-day ice retention cooler with temperatures 40 F or lower.. We monitor temperatures using a $17 electronic thermometer from Amazon that monitors the coach temperature and has two remote sensors which place as appropriate depending up whether we are using a cooler.
2. Pre-cool: If you are unable to connect to shore power or if driveway is slopped too much, recommend pre-cooling the refrigerator with frozen water bottles. 3-way refrigerators tend not to be very good at cooling from a high temperature. They are much better at maintaining a temperature once that temperature has been achieved (by pre-cooling).