We currently carry a 13lbs fluke (Danforth/Fortress style) as our primary anchor and an 8lbs fluke as our backup anchor. Here in Lake Michigan, we typically anchor in sand, mud, and weedy bottoms (in that order). We have 20' of chain (not sure the size) attached to our 100' rope rode. We also carry an 8lbs mushroom to send down the rode as a messenger for extra weight if needed. We've always done just fine with the 13lbs fluke anchoring for a couple hours or the occasional overnighter in good weather.
However, during our 3 month cruise this coming summer we hope to anchor out at least half the time. I expect many of the bottom types to be as above (sand/mud/weeds) but know of a few anchorages where rocks/boulders will be prominent, particularly around Garden Island.
I'm considering picking up either a 22lbs or 33lbs claw/Bruce-type (Lewmar Horizon) anchor to act as our primary anchor. Will this be adequate for a good night's rest and peace of mind? I certainly hope so. I think a claw anchor will be a good compliment to our flukes. Flukes are noted to hold fairly well for their weight in sand and mud, but do little in gravel, rocks and boulders. Claws are reputed to hold well over a wide-range of bottom types, including rocks/boulders. Fishermen-style anchors also hold well in rocks (and little else!) but I don't have the space or back to carry a fishermen-style anchor. Keep in mind our boat is 28.5' and ~8,000lbs dry weight. Also, we don't have a bow roller or good bow storage for anything other than a fluke hanging on the bow rail because of our oversized bow cleats and aluminum toe rail covering the entire edge of the bow. A claw anchor would have to be stored in the cockpit lazerette.
Budget is a factor, and therefore I don't think the highly rated Rocna or Manson Supreme will be realistic this season. Another popular anchor is the plow-style Lewmar Delta. Deltas are supposed to be good for sand, mud and clay but not so much for rocks. While not as expensive as Rocnas and Mansons, a Delta is still about $100 more than a comparable claw. I anticipate that 75% of the time we'll be anchoring in sand/mud/weeds. The remaining 25% of the time might be in rocks/boulders. Does a claw (Lewmar Horizon) still make sense as a primary for our needs? I believe it does. Claws are relatively very affordable and hold well in many situations if sized properly. The downside is that we'll have to deal with the weight of at least 20' of chain rode and a 22 or 33lbs claw without the assitance of a windlass, in addition to finding storage for the beast.