Bolivian Rams hands down - for all the young Bolivian Rams you see in the shops and most of the internet to be fair are quite dull and a bit funny looking as adults they are quite stunning in their own right, all their fins get bright red edges to all their fins and they get trailing threads to the fins as well which keep this luminous red through out, the body takes on a yellow colour and speckling like their larger cousins Geophagus develops behind the gills on the body and a little around the face.
But the main reason is just because German Blue Rams dont survive for their full life span in community tanks. It varies in success levels between keepers with some living for a matter of weeks but others make it into full life span of 5 years and many dieing in between the two.
I think this is down to how closely they are related to the wild fish used to breed the stock. The further away from the wild fish I think have a better chance of living in whats classed as a community setting.
Fish use the ph and resulting nutrients and levels to grow and temperature they live in dictates their metabolism and also works with their respiratory and breathing system. So when a fish like this does not have its ph needs and temperature needs met, it develops deficiencies in these areas.
In other species like some central american cichlids who need a high ph and flowing water if these are not met it is common for some of them to develop bone problems, a lot of central american cichlids kept in low (for them) ph often have bumpy heads which can be a sign of this.
In contrast a relative of the Rams (both species) is the Gymnogeophagus who need a cooling period to survive in a tank setting. This means that across winter their tanks have to cool naturally away from the tropical temperatures of their summer months. If this is not met they often (nearly always) die off after 18 months because the cooling period is part of their evolution to survive in their wild setting and when not given this cool period the parts of the fish that respond to this dont do what they need to do and it literally kills them.
So what Im saying is wild rams and the closer to wild ram lines have to have their needs met which is high temperatures and low ph but the further from wild and more domestic strains can survive in community tanks ie neutral ph and average temperatures. But how to predict how close to wild these fish are is pretty much impossible - even the people in the fish shop will rarely know how far removed they are from the fish. Also strains like electric blue and gold etc are not necessarily safe as breeders will often cross the strain with wild fish before sending them to the shops to provide them with quality genes to survive but in turn giving them the needs of the wild fish as well.
Though all that said there are dozens of other dwarf cichlids that can work in the same tanks as rams and in place of them like Laetacaras and Apistos - Nannacara, Biotodoma, Discrossus (spelling) - even dwarf pikes like Crenicichla Regini can thrive in neutral ph and community settings. And often in most of the species they are more peaceful than rams and arguably more colourful - for example - Laetacara sp.Buckelkopf - incredible colours to this fish yet it only takes roughly a 6-8 inch square territory
Wills
/www.fishforums.net/index.php?/topic/339504-a-southerners-bolivian-ram-journal/
) for me is GBR with Rummy Nose Tetras and Sterbai Cories all of them like high temps and low ph and the tank would be really nice too even on a small scale. Just thinking if your a fan of both those fish why not do a softwater tank? Get some Almond Leaves which lower the ph in your tank naturally and are much less complicated than peat filtration and much much much safer than using ph chemicals. 
