Is it worth to train on eolymp? Are problems well-set? Are there strong test cases?

Found some nice topic wise contest

Graphs — https://www.eolymp.com/en/contests/32919

Trees — https://www.eolymp.com/en/contests/30114, https://www.eolymp.com/en/contests/21224

Bipartite graphs — https://www.eolymp.com/en/contests/30008

0-1 BFS — https://www.eolymp.com/en/contests/26719

DSU — https://www.eolymp.com/en/contests/21411

DFS + Cycles + Cactus — https://www.eolymp.com/en/contests/21451

Flows and matching — https://www.eolymp.com/en/contests/21201

Topological sorting — https://www.eolymp.com/en/contests/21136

DFS — https://www.eolymp.com/en/contests/21097

Graph representation — https://www.eolymp.com/en/contests/21096

Sweeping line — https://www.eolymp.com/en/contests/20844

Dijkstra — https://www.eolymp.com/en/contests/19094

DP — https://www.eolymp.com/en/contests/17887

SCC — https://www.eolymp.com/en/contests/17029

Bitmasking DP — https://www.eolymp.com/en/contests/14738

Bridges, articulation points — https://www.eolymp.com/en/contests/12669