hello can any of you lads recommend a decent core drill to buy,,,ive had enough of hiring them and fancy my own,,,the last couple Ive hired one nearly tore my arms out the sockets when drilling around 10 holes,,,not sure what make it was,,,kept spinning out of my grip no matter how tight i held on,,,too much power???,,,the other was a marcrist which worked like a dream and cut through the wall like a hot knife through butter......