everyone will tell you the kit they have is the best, but I did not mean it in that way. I like things that are perhaps not so mainstream. An HX is a doddle to descale if you need to, only having one boiler. I am not saying all dual boilers are difficult to descale as some have drain taps. But, if you question what you need. A dual boiler lets you turn the steam boiler off which is great if you do not take milk, but not as good if you do. If you make just a couple of drinks at a time, then there is no real advantage to any machine. If you make several drinks on the trot on a regular basis then recovery time and temp feature, but, this is a coffee forum and so many of us have kit which we do not really need if the truth were known. You can have the best kit in the world but you still have to know how to use it!
The L1 and LR come tank fed but you can get plumb in kits for them, but to me, the whole point is to have a quiet machine, so I could never own a lever which was not plumbed in, if that makes sense