Well, that really depends on where you start out! :) In Norway 4cM was the norm in the olden days (that's before I started playing). And unlike in UK, the norm was up-the-line bidding, opening the lowest of two 4-card suits. Thus 4-3-3-3 was the only hand with 4-card spades that was opened 1♠. In the 70s, a standard system evolved, where 1♠ promised 5 and you opened 1♣ with 4-3-3-3. This was the norm (and still is in fact for most players) up to the early 90s, when some (juniors mostly) started playing 1♥ showing 5, unless 44M. Thus 4-3-3-3 and 3-4-3-3 opened 1♣ and 1♦ promised 4 (as before). This is very easy to play (for those coming from 4c♥, probably harder for 5cM players). Not raising partners spades always promice 5c♥. Only in competitive sequences you might be unable to sort out wheather opener has 44M or 5c♥, and only occasionally - mostly you're able to sort this out.