Using any symbol for "\limits"

Using my answer at How are big operators defined?, I merely substituted \Lambda instead of \maltese. While the symbols are slightly different vertical heights, one notes the limits are aligned for both the sigma and lambda.

\documentclass{article}
\usepackage{amsmath}
\usepackage{amsfonts}
\DeclareMathOperator*{\foo}{\scalerel*{\Lambda}{\sum}}
\usepackage{scalerel}
\begin{document}
\centering
\[
\sum_{k=1}^6\foo_{i=3}^{k}(f^2(i)f(k))
\]

This is inline: \(\sum_{k=1}^6\foo_{i=3}^{k}(f^2(i)f(k)) \)
\end{document} 

A variation on \bigmaltese:

\documentclass{article}
\usepackage{graphicx}
\usepackage{amsmath}

\makeatletter
\newcommand{\bigGreek}[1]{%
  \DOTSB
  \mathop{% we want it to be an operator
    \mathchoice{\big@Greek\displaystyle\Large{#1}}
               {\big@Greek\textstyle\large{#1}}
               {\big@Greek\scriptstyle\normalsize{#1}}
               {\big@Greek\scriptscriptstyle\small{#1}}%
    }\slimits@
}

\newcommand{\big@Greek}[3]{%
  \vcenter{%
    \sbox\z@{$#1\sum$}%
    \dimen@=0.875\dimexpr\ht\z@+\dp\z@\relax
    #2% font size
    \hbox{\resizebox{!}{\dimen@}{$\m@th#3$}}%
  }%
  \vphantom{\sum}%
}
\makeatother

\newcommand{\bigLambda}{\bigGreek{\Lambda}}

\begin{document}
Here's in text, $\bigLambda_{i=1}^n x_i$, next in display
\[
\bigGreek{\Xi}_{i=1}^n
\bigGreek{\Sigma}_{i=1}^n
\sum_{i=1}^n \bigLambda_{i=1}^n x_i
\]
\end{document}

The answers given assume that a big lambda operator is really what is wanted here. But couldn't the solution in this particular case be just \bigwedge?