In the US, I would recommend either Omega C (6x7) or B (6x6) series, or similar 6x7 Bessler enlarger.
In the UK, I don't know the availability of those enlargers. I would recommend a Durst M60x or even the F60. My M600 stores away in a nice size box, about half the size of the box for the Omega C67. BUT, Durst is out of the enlarger business, so spares have to come off the secondary (eBay) market. Having said that, my M600 has been totally reliable since 1971, only having to replace the lamp. It probably helps reliability that I have the simple B&W condenser head, not the more complicated color head. If you get a Durst, you want to have ALL the parts when you start out. Hunting for missing parts is difficult, time consuming and expensive.
If you want reliability, I would go with a condenser enlarger. That eliminates the complication and potential problem with the color head or power supply, especially if you are not going to print color anyway. You would just use multi-contrast filters for Multi-Contrast paper, which is not difficult to use. The color head would give you the ability to "dial in" the filter for Multi-Contrast paper, more convenient than the MC filters, but at the cost of the color head.