The Megazine is, and always has been a bit of a mixed bag. IMO it doesn't really compare to 2000ad in terms of quality though the lead Dredd strip is often very strong, and there's also occasionally some really great stuff like Tempest and Insurrection.
Bear in mind that the Meg now costs £4.99 and part of that price goes towards the supplementary reprint magazine that may consist of stuff you've read before. Personally I enjoy the reprints, though it's a divisive issue. A lot of the Meg is also now made up of text articles rather than comic strip, which by their nature are a bit hit and miss - I find some of these fascinating, while others go unread.
The Meg doesn't often have jumping on issues (usually only about one a year) so my advice is to just jump on with the current issue. It looks as if Robbie Morrison is on Dredd scripting duties for the next few months, there's also Judge Dredd: The Lost Cases coming soon, which looks fairly interesting, as well as new series of Bato Loco, Judge Anderson and Tempest, and possibly a bit more from Devlin Waugh and Insurrection. If you like the sound of that, give it a try....