No I don't think so, US has the largest audience who is more benefit to websites. I always chose US because of this reason.There is no benefit of hosting in the U.S. (except if you got a lower price and/or better service terms) if you target the UK market only. You;d better stay with an UK host.
I don't understand this.Unless you have a very busy and large site it will be hard to notice much difference.
Yes it's thing I am thinking about. One more thing, I think US host is quality than a UK host but I can not clarify this factor.It depends on the website purpose. If you are looking to sale services , products in UK market then that website should be hosted in UK itself showing that you are local provider for UK and have existence which is actually an advantage. Having office in UK and website hosted in US is logically not recommended. Generally people do such things for cost cutting as UK and US bandwidth rates as well as hosting prices are different.