I think sealing and resting is the key to not being dry. I always get silverside I melt a large knob of butter pour it over the joint season chop an onion (skin on) put onion in roasting dish (sometimes I smother joint in mustard at this point delicious!) then into oven at 200 degrees for 20 mins to seal cook for further hour and half approx depending on size rest while cook sides so 40mins or so. Use cooking juices for gorge gravy
I do a pot roast, usually with silverside. I usually just use water, but sometimes red wine instead. 160 degrees for about 3 hours. Probably about an inch of water in the bottom of a metal roasting tin with a lid. I baste it every hour or so, and make sure it isn't drying out.
Just fish it out of the liquid at the end to carve, and use the remaining liquid to make gravy while it rests.
I'm not very confident about roasting beef & so I always cook my beef on the hob as follows:
Use either brisket or silverside & heat a tbsp of oil in a saucepan & seal the meat on all sides. Then add enough water to cover 2/3rds of the joint & add a couple of beef stock cubes & bring to the boil, then cover & gently simmer for around 2-3 hours depending on the size of the joint. You can turn it occassionally - maybe once every half hour or so. Other than that you just leave it - so no hassle at all! I then take the meat out & wrap in foil & allow to rest while I use the stock the meat has been cooked in to make gravy with (just thicken with some cornflour & add salt if needed) The meat is always moist & so long as you've cooked it long enough it is never chewy & just melts in your mouth - the gravy is always very tasty too & loads of it!!. The cold leftovers are also really nice for sandwiches or to reheat for another meal. HTH